Prostate cancer causes about 40,000 deaths per year in the United States and is the second highest cause of cancer death among males. Each year, there are over 300,000 new cases of this disease. A key goal in diagnosis of cancer is early detection which allows physicians to intervene at a time when tumor growth is at an early stage. A rapid and inexpensive biochemical test for prostate cancer (provided by Metrika's device), in conjunction with digital rectal examination, will greatly assist the physician in providing a diagnosis while the patient is still in the office, and can provide timely feedback on the effectiveness of treatment and on the detection of recurrence. Measurement of both free and total levels of prostate specific antigen (PSA) will help to distinguish malignancy from benign prostatic hyperplasia (BPH). Metrika laboratories will develop the Digital Response Free/Total PSA Rapid Test which is a rapid, single-use, disposable assay based on the simultaneous measurement of both classes of PSA in a serum, plasma or whole blood sample to yield quantitative numerical results. The test device, which will be about the size of a credit card, will combine inexpensive microelectronics and dry reagent immunochemistry. The focus of this proposal is on demonstrating the feasibility of the dry reagent immunoassays and their integration into a breadboard device. This innovative test will be inexpensive, extremely simple to operate and will provide a digital display of results in a few minutes. This technology will benefit physicians and the healthcare system by improving the efficiency of healthcare delivery at the point of care. In addition, patients will not be subject to return office visits, requiring lost time from work and other expenses, and will receive immediate feedback on their status with respect to this highly prevalent form of cancer. PROPOSED COMMERCIAL APPLICATION: The commercial applications of the Digital Response Free/Total PSA Rapid Test are in point of care sites where access to a rapid quantitative analysis is limited or non-existent. Urologists and primary care physicians will initiate and control use of the test which will yield significant economic and patient benefits.